During the construction of houses and buildings doorframes are installed in the building at an early stage. After installation, workers tread upon the threshold in shoes or boots, that carry mortar, dirt and rocks on the soles, Workers wheel or drag equipment into the house or building subjecting the threshold to scraping and impact. Bricks may be placed on the threshold or fall onto the threshold by workmen installing the exterior brick. Mortar, paint and chemicals, such as lacquer or thinner, can drip onto the threshold during varying phases of construction resulting in discoloration or damage. During the acid wash of the exterior brick, hydrochloric acid can fall onto the threshold causing additional discoloration or damage.
Removing dirt, rocks, mortar, paint, thinner, lacquer or acid discoloration from the threshold of a doorway takes one worker from fifteen to thirty minutes per doorway. In a typical residential construction with three doorways, three quarters of one man hour to one and one-half man hours of labor are required for the clean-up. Moreover, the clean-up work cannot remove scratches or dents. If a drop cloth is thrown over the threshold, it may not stay in place, or it will wear out before the construction is completed. More importantly, a drop cloth will be a hazard for workers who may trip over the loose material thereby causing increased expenses through on the job injuries and lost time. Putting tape on the threshold requires a good deal of time and will not survive the entire construction cycle due to the traffic and loads to be borne. Therefore, a need exists for an inexpensive disposable threshold protector that will have sufficient durability to last the entire construction period of the house or building.
Additionally, protection of thresholds is beneficial during moving of furniture, installation of new doors and during remodeling of existing buildings.
The prior art does not disclose such a protector. There are many examples of thresholds; however, no device has been patented to provide for the protection of the threshold during the construction of the house or building. U.S. Pat. No. 4,492,062 to Levenez discloses a window sill assembly for protecting and covering an existing window sill at the base of the window. The device is meant for permanent installation and is not adaptable to door thresholds.